Every idea

Ideas 18151–18300 of 19934.

Name	Kind	Subject
Wilks' theorem	Theorem	Statistics
Funk transform	Concept	Integral transforms, operational calculus
Munk's wind-driven circulation model	Definition	Geophysics
McKay conjecture	Theorem	Group theory and generalizations
Tight and overtwisted contact structures	Concept	Manifolds and cell complexes
Parker spiral	Definition	Astronomy and astrophysics
Jackson's inequality	Theorem	Approximations and expansions
Instant centre of rotation	Concept	Mechanics of particles and systems
Null-homotopic map	Definition	Algebraic topology
Prandtl–Glauert transformation	Proposition	Fluid mechanics
Bogoliubov transformation	Concept	Quantum theory
Gibbs–Bogoliubov inequality	Theorem	Statistical mechanics, structure of matter
Screw theory	Definition	Mechanics of particles and systems
Finitely generated algebra	Concept	General algebraic systems
Kolmogorov extension theorem	Theorem	Probability theory and stochastic processes
Abstract polytope	Concept	Convex and discrete geometry
Uniqueness of solutions given initial values	Proposition	Difference and functional equations
Elementary subgroup	Definition	K-theory
Picard's theorem for systems with continuous partial derivatives	Theorem	Ordinary differential equations
Triangle center	Concept	Geometry
Griffith criterion	Proposition	Mechanics of deformable solids
Maximal order	Definition	Associative rings and algebras
Quasivariety	Concept	General algebraic systems
Discrete harmonic function	Concept	Potential theory
Bridge number	Definition	Manifolds and cell complexes
Gale diagram	Definition	Convex and discrete geometry
Electromagnetic tensor	Concept	Optics, electromagnetic theory
Normal modes of the Earth	Definition	Geophysics
Solution of recurrences by generating functions	Concept	Difference and functional equations
Rodrigues' rotation formula	Proposition	Mechanics of particles and systems
Fracture mechanics	Definition	Mechanics of deformable solids
Linear and stable summation methods	Definition	Sequences, series, summability
Propagation of uncertainty	Concept	Numerical analysis
Mean-field game	Concept	Game theory, economics, finance, and other social and behavioral sciences
Matrix population model	Concept	Biology and other natural sciences
Costate equation	Concept	Calculus of variations and optimal control; optimization
Dimension group	Concept	K-theory
Eddington luminosity	Concept	Astronomy and astrophysics
Pfister form	Definition	Number theory
Information content	Definition	Information and communication theory, circuits
Menger sponge	Example	General topology
Henselian ring	Definition	Commutative algebra
Lebesgue's density theorem	Theorem	Measure and integration
Uniqueness of Haar measure	Theorem	Measure and integration
Bounded symmetric domain	Definition	Several complex variables and analytic spaces
Classifying space	Concept	Algebraic topology
Euler transform	Concept	Sequences, series, summability
Riemann–Lebesgue lemma for abelian groups	Theorem	Abstract harmonic analysis
Stability of matter	Theorem	Quantum theory
G-structure	Definition	Differential geometry
Inverse scattering transform	Definition	Dynamical systems and ergodic theory
Wigner distribution function	Definition	Quantum theory
Diffeomorphism group	Example	Global analysis, analysis on manifolds
Borsuk's conjecture	Counterexample	Convex and discrete geometry
Bulk modulus	Definition	Mechanics of deformable solids
Focal mechanism	Definition	Geophysics
Cobordism	Definition	Manifolds and cell complexes
Van Cittert–Zernike theorem	Theorem	Optics, electromagnetic theory
Estimating equations	Concept	Statistics
Gosper's algorithm	Definition	Special functions
MLC conjecture	Conjecture	Dynamical systems and ergodic theory
Regularization of ill-posed problems	Concept	Numerical analysis
Rogers–Ramanujan continued fraction	Definition	Number theory
Fujiki class C	Definition	Several complex variables and analytic spaces
Bayesian search theory	Concept	Operations research, mathematical programming
True quantified Boolean formula	Problem	Computer science
Forgetful functor	Concept	Category theory; homological algebra
Pseudovariety	Definition	General algebraic systems
Cartan's test for involutivity	Theorem	Global analysis, analysis on manifolds
Commutative diagram	Concept	Category theory; homological algebra
Lelong number	Concept	Several complex variables and analytic spaces
Cox–de Boor recursion	Theorem	Approximations and expansions
Inertia tensor and principal axes	Concept	Mechanics of particles and systems
Chemical potential	Concept	Classical thermodynamics, heat transfer
Morlet wavelet	Example	Harmonic analysis on Euclidean spaces
Riemann–Lebesgue lemma	Theorem	Harmonic analysis on Euclidean spaces
Bézout domain	Definition	Commutative algebra
Cosmological constant	Concept	Relativity and gravitational theory
Proof that cosets have the same cardinality as the subgroup	Proof	Group theory and generalizations
BCMP network	Theorem	Probability theory and stochastic processes
Small oscillations about equilibrium	Concept	Mechanics of particles and systems
Chronology protection conjecture	Conjecture	Relativity and gravitational theory
Riesz–Fischer theorem	Theorem	Functional analysis
Vorticity equation	Definition	Fluid mechanics
Hohenberg–Kohn theorems	Theorem	Quantum theory
Schottky group	Definition	Functions of a complex variable
GAGA	Theorem	Several complex variables and analytic spaces
Medial magma	Definition	Group theory and generalizations
Orbital perturbation	Concept	Mechanics of particles and systems
Scattering theory	Definition	Quantum theory
Stokes' law	Theorem	Fluid mechanics
Reynolds equation	Definition	Fluid mechanics
Fubini's theorem for series	Theorem	Sequences, series, summability
Jack function	Concept	Combinatorics
Kullback–Leibler divergence	Definition	Information and communication theory, circuits
Simplicial set	Concept	Category theory; homological algebra
Asteroseismology	Definition	Astronomy and astrophysics
Polhode	Concept	Mechanics of particles and systems
Hilbert class field	Concept	Number theory
Method of steepest descent	Definition	Approximations and expansions
Parameterized complexity	Definition	Computer science
Newman's lemma	Lemma	Computer science
Square-integrable kernel	Concept	Integral equations
Shape optimization	Problem	Calculus of variations and optimal control; optimization
Closed immersion	Concept	Algebraic geometry
Metapopulation model of Levins	Concept	Biology and other natural sciences
Eremenko's conjecture	Conjecture	Dynamical systems and ergodic theory
Parabolic and hyperbolic Riemann surfaces	Definition	Functions of a complex variable
Riemann P-symbol	Concept	Special functions
Section of a vector bundle	Concept	Algebraic topology
Wang sequence	Theorem	Algebraic topology
Engel subalgebra	Definition	Nonassociative rings and algebras
Invariant set	Concept	Ordinary differential equations
Koebe quarter theorem	Theorem	Functions of a complex variable
Borromean rings	Example	Manifolds and cell complexes
Tensor field	Concept	Differential geometry
Fictitious play	Definition	Game theory, economics, finance, and other social and behavioral sciences
Lee–Yang zeros	Definition	Statistical mechanics, structure of matter
Nussinov algorithm	Definition	Biology and other natural sciences
Poisson integral for the half-space	Theorem	Potential theory
Algebraic number field	Definition	Number theory
Euler's thirty-six officers problem	Problem	Combinatorics
Pseudocomplement	Definition	Order, lattices, ordered algebraic structures
Yoneda Ext and extensions	Theorem	Category theory; homological algebra
Logic optimization	Problem	Information and communication theory, circuits
Asymptotic stability of linear recurrences	Theorem	Difference and functional equations
Constraint	Definition	Operations research, mathematical programming
Retarded potential	Definition	Optics, electromagnetic theory
Tangent bundle	Concept	Global analysis, analysis on manifolds
Proximity space	Concept	General topology
Isobaric process	Concept	Classical thermodynamics, heat transfer
Brill–Noether theory	Definition	Algebraic geometry
Formally real Jordan algebra	Concept	Nonassociative rings and algebras
Group representation	Concept	Group theory and generalizations
Vitali set	Counterexample	Measure and integration
Majorization	Definition	Real functions
Magnetic scalar potential	Concept	Optics, electromagnetic theory
Fox–Wright function	Definition	Special functions
Scleronomous constraint	Definition	Mechanics of particles and systems
Lorenz system	Example	Ordinary differential equations
Minkowski–Bouligand dimension	Concept	Measure and integration
Oppenheimer–Snyder model of collapse	Example	Relativity and gravitational theory
Kernel	Definition	Category theory; homological algebra
Locally finite variety	Definition	General algebraic systems
Kakeya needle problem	Problem	Measure and integration
Girth	Definition	Combinatorics
Urysohn integral equation	Concept	Integral equations
Hurwitz's theorem on composition algebras	Theorem	Nonassociative rings and algebras
Fiber of a morphism	Definition	Algebraic geometry
Cauchy filter	Concept	General topology